Nope, tried that yesterday after i saw this post. Didn’t help this time. Singleplayer like said.
Then checked on server (regular build), it was working perfectly. Again, it’s a pure SP thing, and it’s a shame, because it’s a great looking dungeon, important in the lore.
This problem feels the same to the lack of bosses (on singleplayer) in the Siptah crypts. And this issue has been fixed in the latest (2.5) Testlive patch.
I hope they will repair the Palace of the Witch Queen in the same way.